Rock-drill clamp



i EA u YT... n n K 1% R (N0 Model.)

Patented May 2, 1893.

Tar-j as ya, 4

mums Farms ca. mow-umo UNITED STATES PATENT OFFICE.

JOHN GEORGE LEYNER, OF DENVER, COLORADO.

ROCK-DRILL CLAMP.

SPECIFICATION forming part of Letters Patent No. 496,573, dated May 2, 1893.

Application filed December 19, 1892. Serial No. 455,677. (No model.)

To all whom it may concern.-

Be it known that I, JOHN GEORGE LEYNER, a citizen of the United States of America, residing at Denver, in the county of Arapahoe and State of Colorado, have invented certain new and useful Improvements in Rock-Drill Clamps; and I do declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being bad to the accompan ing drawings, and to the letters of reference marked thereon, which form a part of this specification.

Myiuvention relates to improvements in clamps for adj ustably securing rock drills to drifting and stopping bars, or columns, which in tunnels, shafts and drifts are braced between the walls to support in various positions and angles, rock drilling machines.

The objects of my invention are, first, to provide a clamp in which the drill can be swiveled, without loosening the clamp on the drifting bar or column; second, to provide a clamp simple in construction, economical in cost, durable, and highly efficient in use. I attain these objects by the mechanism illustrated and described in the following drawings and specifications, in which:

Figure 1 represents a longitudinal vertical section through the center of my improved clamp, and a partial vertical section through a rock drill shell. Fig. 2 represents a perspective View of myimproved clamp attached to a section of a drifting bar or column.

Similar letters of reference refer to similar parts throughout both the views.

In Fig. 1, A represents a partial sectional View through the center of a rock drill shell. The cylinder of the drill is not shown, not forming a part of my invention, but in steam or air rock drills, it is adapted to the ways, A, of the shell, and it is fed back and forth in the shell by the screw A which is arranged in the neck A and is provided with a crank A", for manipulation. The bottom of the shell is provided with acircular convexed hub B, which radiates from the body of the shell, thus making the end of the hub of larger diameter than the portion close to the shell.

O designates a cast block forming one half of the clamp. At the top it is provided with a semicircular concave recess D adapted to match and surround one half of the said hub B.

E designates a metal block which forms the opposite half of that portion of the clamp which surrounds the drifting bar. The top of this half is even with the bottom of the recess D, thus forming a bearing on both for the bottom of the hub B. A hole F is formed partially in each block, which hole is of a size to receive and surround the drifting bar or column G, with the exception of a small space between the jaws. Below the hole F, and close to it, the blocks are clamped together by the bolt H which passes freely through each at right angles to the hole. A recess I, is formed in the block E adapted to inclose the head of the bolt and thus prevent its turning when its nut J is manipulated.

Between the top of the hole F and the bottom of the concave recess D, which is level with the top of the block E and located centrally through both blocks parallel with the bolt H, is a bolt K. At the point L, where this bolt enters the block E, it is enlarged into a collar M, preferably square, which fits in a recess N formed in the said block adapted to inclose it, to prevent its turning when its nut O is manipulated. From the collar M the bolt extends freely through the arm P. The lower end of this arm is loosely pivoted in a semicircular recess Q, formed in the side of the block E. Its upper end'B is formed into a semicircular concave jaw, arranged opposite and in the same plane with the convexed recess D of the block 0. It is concave to match the similar shape of the hub B, and with the recess jaw D of the block C, almost entirely surrounds it.

The operation is as follows: The clamp is placed on a drifting bar, and the blocks 0 and E are clamped tightly to it by tightening the nuts J and O of the bolts H and K, which are arranged one above, and the other below the drifting bar hole. It will be noticed that the nut 0 draws the collarM of the bolt K against the block E, and thus clamps the blocks together on the drifting bar, independent of the device for clamping the hub to the drill shell. The hub of the rock drill is then placed in the recess jaw D of the block 0, resting on the bottom of the said recess and on the top of the block E. The arm P is then fed by the nut S to clamp the hub tightly in the concave circular recess formed by the jaws R and D.

It is occasionally necessary when drilling rock to withdraw the drill bit from the hole, and spoon, or pump out the drillings. To accomplish this with my clamp, it is not necessary to move the drill out of alignment with the hole, but simply to retract the drill cylinder and bit by means of the screw A and then to loosen the arm P by manipulating the nut S and swiveling the drill to one side of the hole. It is obvious that this can be accomplished without loosening the clamp on the drifting bar, consequently when the drill is reset in the hole, its alignment is assured.

Having described my invention, what I claim as new, and desire to secure by Letters Patent, is-

1. The combination in a rock drill drifting bar clamp of the blocks 0 and E provided with a hole formed partially in each, of bolts connecting them, one above andthe other below the said hole arranged transversely wit, the top bolt provided with ashoulder bearing in a recess adapted to receive it in the block E and the bolt extending beyond the said shoulder; of an arm pivoted to a recess in the said block E and also to the end of the said bolt, said arm having a semicircular concaved jaw adapted to partially surround a con vexed hub forming a part of the drill shell; of a semicircular concaved recess formed in the top of the block 0 adapted to partially surround the said hub of the drill shell arranged even with the bottom of the said recess and supporting with it the bottom of said hub, the combination operating to clamp the block 0 and the said arm to the said drill shell hub and the blocks E and O to the drifting bar, as herein specified.

2. The combination with the drifting bar and convex hub of the blocks (J and E provided with a hole adapted to receive the said drifting bar of the bolt K passing through the said blocks above the said hole, threaded at both ends, and provided with a head or collar adapted with one of the said threaded ends to clamp the tops of the said blocks together, of the bolt H passing through the said blocks below said hole; the said bolts operating to clamp the said blocks upon the drifting bar, with the movable arm P pivoted to the said block E, and to the said bolt K and provided with a semicircular concave jaw, and with the semicircular concave recess R of the block 0 adapted in combination with the said movable arm and nut S on one end of bolt K to surround and clamp the said convex hub to the blocks, and operating by manipulation of the nuts J and O to clamp the said blocks to said drifting bar as herein set forth and described.

In testimony whereof I afiix my signature in presence of two witnesses.

JOHN GEORGE LEYNER.

\Vi tn WALTER MERLE MoRRIs, ARTHUR AUGUSTUS Summit. 

